Light leaks through the focus distance window under certain circumstances. It rarely actually affects an image though. It requires that more light shines on the distance scale than comes through the lens elements(such as when using heavy ND filters). It also seems to only happen around 40-50mm. So basically only when shooting just as you shot these images. A piece of dark tape over the window when taking these images will prevent it in the future. Nikon has supposedly updated the construction of current lenses to correct it.

Wow, if something that affects basic functionality happened on a car or many other consumer goods there would be a recall. I guess 24-70 owners are out of $2000 with no recourse. Good to know. Given that distance scales are largely useless on lenses nowadays, I would be tempted to stick electrician's tape on it of I owned the 24-70.

Taping over the distance scale will be the easiest fix. However, Nikon apparently has a fix for the issue. Since the issue isn't noticable under most shooting conditions there hasn't been a 'huge' outrage. I'd send it to Nikon, including the pictures, and they should be able to take care of it.

GroovyGeek wrote:
Wow, if something that affects basic functionality happened on a car or many other consumer goods there would be a recall. I guess 24-70 owners are out of $2000 with no recourse. Good to know. Given that distance scales are largely useless on lenses nowadays, I would be tempted to stick electrician's tape on it of I owned the 24-70.

It is not at all like that. Automobiles and some consumer products are recalled when there is a safety hazard. Non-hazardous defects in consumer products are usually covered by warranties. In case the defect is pervasive and prevalent, the manufacturer may choose to advise consumers to return the product for free repair/replacement to fend off possible class action suits that the product is not fit for use. However, they have to decide on a case by case basis.

The 24-70 Nikkor defect is similar in a way to the first early defective batch of Canon 24-105 lenses. Canon elected to replace the entire lens instead of repairing them, since the numbers involved were few (1000 or so) and it was caught very early. I think the 24-70 Nikkor situation lasted longer than that and/or a larger number of lenses was affected.